This Holden model number is the C60S-based "Tractors, Artillery
(Aust) No6"
Here's the WO 78 segment from my
database :
Artillery tractor No 6
WO78 C60S Perth 28442P00185
WO78 C60S Perth 2844400207P WR3853527 - 7.7.43 -
WO78 C60S Melbourne 2844200690M PR3874479 - 8.9.43 73863
WO78 C60S Melbourne 2844200694M PR3874466 - 10.9.43 -
WO78 C60S Melbourne 2844200698M PR3874465 - 13.9.43
WO78 C60S Melbourne 2844200711M PR3874368 - 14.9.43 73922
WO78 C60S Melbourne 2844200730M PR3874378 - - -
WO78 C60S Melbourne 2844200735M - - 74046
WO78 C60S Melbourne 2844200742M
WO78 C60S Sydney 2844300565S PR3886562 - - -
WO78 C60S Sydney 28442S00711 - - -